Membrane transport跨膜转运 Xia Qiang(夏强),PhD Department of Physiology Zhejiang University School of Medicine Tel:88208252 Email:xiaqiang@zju.edu.cn
Membrane Transport 跨膜转运 Xia Qiang（夏强）, PhD Department of Physiology Zhejiang University School of Medicine Tel: 88208252 Email: xiaqiang@zju.edu.cn
LEARNING OBJECTIVES Describe how solutes cross cell membranes Explain how charge size and solubility affect solute movement across cell membranes Contrast how transporters, pumps channels work Describe how ion channels are gated Describe how epithelial transport works
LEARNING OBJECTIVES • Describe how solutes cross cell membranes • Explain how charge, size, and solubility affect solute movement across cell membranes • Contrast how transporters, pumps & channels work • Describe how ion channels are gated • Describe how epithelial transport works
Membrane Transport Simple diffusion(单纯扩散) Facilitated Diffusion(易化扩散) Active Transport(主动转运) Endocytosis and exocytosis(出胞与入胞)
Membrane Transport ▫ Simple Diffusion（单纯扩散） ▫ Facilitated Diffusion（易化扩散） ▫ Active Transport（主动转运） ▫ Endocytosis and Exocytosis（出胞与入胞）
Solute racellular flu Electrochemical gradient x X Intracellular fluid nergy Simple Channel mediated Carrier mediated Active transport diffusion diffusion diffusion A B c E Passive transport (facilitated diffusion)
Compartment 1 impartment 2 High solute concentration Low solute concentration One-way flux∴∴∴∵ One-way flux 器Net小…/八∴∴∴∷ Note: the partition between the two com partments is a membrane that allows this solute to move through it Net flux accounts for solute movements in both directions
Note: the partition between the two compartments is a membrane that allows this solute to move through it. Net flux accounts for solute movements in both directions